A pixel-based Spatial Light Modulator (“SLM”) can be used to modulate an incoming light signal. SLMs can be used in many contexts, such as in projection displays, printing, telecommunications, and in other types of light processing. In a telecommunications context, an incoming light signal can have multiple different channels or carrier wavelengths. In these contexts, differing patterns of pixels are used to achieve differing desired performance characteristics of the modulated light signal. A challenge, however, is to determine the pixel patterns, from all the possible pixel patterns, to be used to achieve the desired optical performance characteristics.